The Host Defense Group of the Laboratory of Respiratory Biology, Division of Intramural Research, National Institute of Environmental Health Sciences, headed by Michael B. Fessler, MD now enters its twelfth year at the NIEHS. Publications since the last annual report include: 1. a collaborative report on the use of proteomics to identify effects of ethanol and endotoxin on the macrophage (PMID 29481576) 2. a collaborative report on the effect of sulfite on protein oxidation in the inflamed lung (PMID 29306790) 3. a workshop report on the state of the art for use of proteomics and metabolomics in lung research (PMID 29192815) 4. a review/commentary on cholesterol in lung immunity and inflammation (PMID 29161079) 5. an editorial on carbon dioxide as a potential obesogen (PMID 29090955) 6. an original manuscript on the impact of oral arsenic on pulmonary immunity (PMID 28960179) 7. an original manuscript showing that deletion of the immune response gene Irgm1 in mice causes an autoimmune disorder mimicking the human condition, Sjogren's Syndrome (PMID 28814662) 8. an original manuscript reporting the association of house dust endotoxin concentration and peripheral blood leukocyte counts in U.S. citizens (PMID 28599265) Additional accomplishments since our last report include filing of a provisional patent application by Dr. Fessler on a potential novel strategy for intervening on lung inflammation (U.S. Provisional Patent Application No. 62/664,805 (4/30/18)), service of Dr. Fessler as a reviewer for the U.K. Medical Research Council, and presentation of findings from Dr. Fessler's group, in the form of oral presentations and posters, at several national/international meetings.